Platinum, 18 Karat Pink Gold And Diamond Ring, Rosi Blu. Photo Sotheby's

Set in the center with a round diamond weighing 5.56 carats, flanked by 2 round diamonds each weighing .70 carat, the mounting set throughout with small round diamonds weighing 1.12 carats, and small round diamonds of pink hue weighing .14 carat, size 6½, signed Rosi Blu. Estimate 725,000-825,000 USD

Accompanied by GIA report no. 1122590623 stating that the 5.56 carat diamond is D color, Internally Flawless, with Excellent Cut, Polish and Symmetry; GIA report no. 2116850120 stating that first .70 carat diamond is D color, Internally Flawless, with Excellent Cut, Polish and Symmetry; and GIA Diamond Dossier report no. 2111138288 stating that the second .70 carat diamond is D color, Internally Flawless, with Excellent Cut, Polish and Symmetry.

Platinum And Diamond Ring, Van Cleef & Arpels. Photo Sotheby's

The emerald-cut diamond weighing 9.19 carats, flanked by triangular-shaped diamonds weighing approximately 2.80 carats, size 6¾, signed Van Cleef & Arpels, Estimate 500,000-700,000 USD

Accompanied by GIA report no. 10627762 (dated May 18, 1999) stating that the diamond is D color, VVS2 clarity.

Property From An Important Private Collection

18 Karat White Gold And Diamond Ring. Photo Sotheby's

The emerald-cut diamond weighing 6.47 carats, within a wide white gold band enhanced by geometric motifs, size 6. Estimate 150,000-200,000 USD

Accompanied by GIA report no. 1132529281 stating that the diamond is F color, VS1 clarity.

Pair Of Platinum And Diamond Pendant-Earclips; Photo Sotheby's

Set with 2 pear-shaped diamonds weighing 4.19 and 4.02 carats, surmounted by 2 pear-shaped diamonds weighing 1.56 and 1.51 carats. Estimate 100,000-150,000 USD

Accompanied by GIA report no. 2125590590 stating that the 4.19 carat diamond is H color, SI2 clarity; GIA report no. 5121477350 stating that the 4.02 carat diamond is I color, SI1 clarity; GIA report no. 5121865930 stating that the 1.56 carat diamond is G color, SI1 clarity; and GIA report no. 2121555542 stating that the 1.51 carat diamond is G color, SI2 clarity.

Platinum And Diamond Necklace/Bracelet Combination, Harry Winston. Photo Sotheby's

The graduated necklace set in the center with an emerald-cut diamond weighing approximately 2.25 carats, further set with smaller emerald-cut diamonds weighing 25.56 carats, alternating with marquise-shaped diamonds weighing 13.56 carats, length 14 3/8 inches, converts into two bracelets, lengths 7 and 6¼ inches, necklace can be shortened by removing 1 inch segment, unsigned. Estimate 100,000-150,000 USD

Accompanied by a copy of the Insurance Appraisal from Harry Winston, dated June 24, 1960.

Platinum And Diamond Ring. Photo Sotheby's

The round diamond weighing 5.66 carats, size 6½. Estimate 90,000-120,000 USD

Accompanied by GIA report no. 2135370104 stating that the diamond is H color, VS2 clarity.

Platinum, Gold And Diamond Ring. Photo Sotheby's

Set in the center with an old European-cut diamond weighing 14.02 carats, framed by smaller old European-cut diamonds weighing approximately 3.00 carats, size 5¾. Estimate 80,000-120,000 USD

Property from a New York Estate

Platinum And Diamond Ring. Photo Sotheby's

The emerald-cut diamond weighing 9.99 carats, flanked by tapered baguette diamonds, size 7. Estimate 60,000-80,000 USD

Property From The St. Clair Trust  

Platinum And Diamond Bracelet, David Webb, Circa 1960. Photo Sotheby's

The highly articulated bracelet of foliate design set with old European-cut and round diamonds weighing approximately 31.00 carats, length 6¾ inches, signed Webb. With signed box. Estimate 60,000-80,000 USD

Together with a letter of authenticity from David Webb.

Property of A Private Collection

Platinum And Diamond Band Ring. Photo Sotheby's

Set with oval diamonds weighing 1.05, 1.03, 1.03, 1.02, 1.02, 1.02, 1.01, 1.00, 1.00, .95, .91, .90, and .90 carats, size 6. Estimate 50,000-75,000 USD

Accompanied by 13 GIA reports stating that the diamonds are D to F color, VS1 to VS2 clarity.

Platinum And Diamond Ring. Photo Sotheby's

The pear-shaped diamond weighing 6.56 carats, flanked by tapered baguette diamonds weighing approximately .70 carat, size 6½. Estimate 50,000-70,000 USD

Accompanied by GIA report no. 2135252778 stating that the diamond is K, Faint Brown color, VS1 clarity; together with a letter from the GIA stating that the diamond has been determined to be type IIa.

Pair Of Platinum And Diamond Earclips. Photo Sotheby's

Designed as styled hoops set with baguette diamonds weighing approximately 2.00 carats, 2 larger round diamonds weighing approximately 2.65 carats, and smaller round diamond weighing approximately 9.00 carats. Estimate 20,000-30,000 USD

Property of a Florida Collector.

 Sotheby's. Magnificent Jewels, New York 20 september 2011 www.sothebys.com